RFID (Radio Frequency Identification, radio frequency identification) is a kind of noncontact automatic identification technology, also known as radio frequency identification, and is a kind of communication technology that can identify specific targets and read and write relevant data by radio signals without identifying mechanical or optical contact established between the system and the specific targets. The RFID technology has a broad application prospect and has been gradually applied to all aspects of industrial production and daily life, and especially in the aspect of libraries, more and more libraries begin to adopt the RFID technology to replace the original bar code systems.
The traditional library bar code system has the following disadvantages: 1. a bar code adopts the laser technology, when the information of a book needs to be scanned, the book must be manually opened, and the bar code in the book is scanned by using a scanner, thereby wasting a lot of labor; 2. the bar code can store fewer data, and the data are not encoded, so that the confidentiality and security of the data are not high; 3. the bar code can only identify the producer and the product, and cannot identify the specific product. Radio frequency identification (RFID) technology can solve these problems and mainly has the following outstanding advantages: 1. non-contact reading: an RFID tag can be read through a non-metallic material without being in direct contact with the tag, therefore the identification work is accomplished without manual intervention, and automation is realized; 2. large data storage capacity: the data storage capacity of the RFID tag is large, and the data on the tag can be encrypted, updated, read and written at any time, so that the RFID tag is especially suitable for storing a large number of data or the situation that to-be-stored data on articles change frequently; 3. high reading and writing speed: the RFID technology can identify high-speed moving objects and can identify a plurality of tags at the same time, so that the operation is quick and convenient; 4. high data security: besides password protection of the tag, security management of the data part can be realized by using some algorithms, such as DES, RSA, DSA, MD5 and the like, a reader-writer and an electronic tag can realize mutual authentication so as to achieve secure communication and storage. It can be said that the introduction of the RFID technology has brought about great convenience to the library management. At present, the RSSI signals of the RFID tags are not used in the identification of book placement postures in the libraries. In the libraries, due to the carelessness of some readers, the books are randomly placed on other books occasionally, resulting in disorder of book arrangement, which affects the management of the books in the libraries, these books horizontally placed by mistake can be automatically identified by using RFID tag signals, thereby facilitating the management of the books by librarians, ensuring neat and orderly appearance of the libraries, and also bringing convenience to the readers to find books.